Mower Muffler

i have a craftsman push mower model # 917.388851, oil is coming out of the muffler. What should i do?

it's the breather (two bolts and $3) or bad valve seals (overhaul time).

The bad carb crap posted earlier is bs.

I fixed mowers for a pro shop for 5 years.

Added:
Almost forgot. The number one reason for this is overfilling the oil. Many of the newer mowers have a DIPSTICK and you are not supposed to fill the whole engine with three quarts of oil. It's amazing how many people do this...probably because for years the system had us fill to the rim of the little oil fill. Do not add too much oil. Your engine has a dipstick. Manual below.

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Time Remaining: 13h 12m
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Time Remaining: 13h 21m
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Time Remaining: 13h 58m
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Time Remaining: 14h 2m
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Time Remaining: 14h 12m
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Time Remaining: 14h 34m
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Time Remaining: 14h 35m
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Time Remaining: 14h 36m
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Time Remaining: 14h 36m
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Time Remaining: 14h 41m
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Time Remaining: 14h 41m
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Time Remaining: 14h 41m
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Time Remaining: 14h 41m
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Time Remaining: 14h 41m
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Time Remaining: 14h 41m
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